From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Thu, 27 Dec 2018 18:40:19 +0000 (+0000)
Subject: docs: Improve documentation and parsing for pci=
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=01397478f29239a0e22655ff1a35f4ff9577b63b;p=people%2Fpauldu%2Fxen.git

docs: Improve documentation and parsing for pci=

Alter parse_pci_param() to use parse_boolean(), so the sub options
behave like other Xen booleans.

Update the command line documentation for consistency.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-acked-by: Juergen Gross <jgross@suse.com>
---

diff --git a/docs/misc/xen-command-line.pandoc b/docs/misc/xen-command-line.pandoc
index 0d4268d1ff..7aaf922265 100644
--- a/docs/misc/xen-command-line.pandoc
+++ b/docs/misc/xen-command-line.pandoc
@@ -1500,13 +1500,12 @@ This option is ignored in **pv-shim** mode.
 > Default: `on`
 
 ### pci
-> `= {no-}serr | {no-}perr`
+    = List of [ serr=<bool>, perr=<bool> ]
 
-> Default: Signaling left as set by firmware.
-
-Disable signaling of SERR (system errors) and/or PERR (parity errors)
-on all PCI devices.
+    Default: Signaling left as set by firmware.
 
+Override the firmware settings, and explicitly enable or disable the
+signalling of PCI System and Parity errors.
 
 ### pci-phantom
 > `=[<seg>:]<bus>:<device>,<stride>`
diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 93c20b9b06..8108ed5f9a 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -188,37 +188,25 @@ custom_param("pci-phantom", parse_phantom_dev);
 static u16 __read_mostly command_mask;
 static u16 __read_mostly bridge_ctl_mask;
 
-/*
- * The 'pci' parameter controls certain PCI device aspects.
- * Optional comma separated value may contain:
- *
- *   serr                       don't suppress system errors (default)
- *   no-serr                    suppress system errors
- *   perr                       don't suppress parity errors (default)
- *   no-perr                    suppress parity errors
- */
 static int __init parse_pci_param(const char *s)
 {
     const char *ss;
     int rc = 0;
 
     do {
-        bool_t on = !!strncmp(s, "no-", 3);
+        int val;
         u16 cmd_mask = 0, brctl_mask = 0;
 
-        if ( !on )
-            s += 3;
-
         ss = strchr(s, ',');
         if ( !ss )
             ss = strchr(s, '\0');
 
-        if ( !cmdline_strcmp(s, "serr") )
+        if ( (val = parse_boolean("serr", s, ss)) >= 0 )
         {
             cmd_mask = PCI_COMMAND_SERR;
             brctl_mask = PCI_BRIDGE_CTL_SERR | PCI_BRIDGE_CTL_DTMR_SERR;
         }
-        else if ( !cmdline_strcmp(s, "perr") )
+        else if ( (val = parse_boolean("perr", s, ss)) >= 0 )
         {
             cmd_mask = PCI_COMMAND_PARITY;
             brctl_mask = PCI_BRIDGE_CTL_PARITY;
@@ -226,7 +214,7 @@ static int __init parse_pci_param(const char *s)
         else
             rc = -EINVAL;
 
-        if ( on )
+        if ( val )
         {
             command_mask &= ~cmd_mask;
             bridge_ctl_mask &= ~brctl_mask;